1. Field of the Invention
The present invention relates to an amplifier and, for example, to an outdoor type amplifier placed on the top of a telephone pole and used for a radio communication system for a portable telephone.
2. Description of the Related Art
An outdoor type amplifier, which is placed at a high position such as on the top of a telephone pole or on the roof of a building, is used for amplifying a radio wave in a portable radio-phone system such as a portable telephone. One example of conventional outdoor type amplifiers placed on the top of a telephone pole is shown in FIG. 4.
This amplifier is composed of an amplifier box 101 and one amplifier part 102 built therein. A door 103 for maintenance and inspection is provided on the front of the amplifier box 101. A rubber packing 104 is provided on the mating face of the door 103 where the door 103 is mated with the amplifier box 101, and the door 103 is closed in the state where the door 103 is mated with the packing 104 by fastening screws 105.
On the back side of the amplifier box 101 is provided a radiator 106 for dissipating heat. On the back of the amplifier box 101 is provided a fixing hardware 107 and by fixing the fixing hardware 107 to a telephone pole or the like with fixing bolts 108, the amplifier is fixed to the telephone pole or the like. A high-frequency connector 109, a signal connector 110, a power source connector 111 and the like are connected to the amplifier part 102 in the amplifier box 101 from the outside.
When the amplifier having the above configuration needs to be dismounted and repaired or replaced, the high-frequency connector 109, the signal connector 110, the power source connector 111 are disconnected and further the fixing bolts 108 are removed and then the whole amplifier is dismounted from the telephone pole.
In the above conventional amplifier, when the amplifier is repaired or replaced, because the amplifier part is one, the amplification function of the amplifier is lost, thereby narrowing the service area of the portable telephone, which results in causing inconvenience to the users of the portable telephone.
The present invention has been made in view of this problem and the object of the present invention is to provide an amplifier which does not lose its amplification function even when it is repaired or inspected.
An amplifier according to the present invention to solve the above-mentioned problem comprised a box and a plurality of amplifier parts mounted on the box in such a way that they can be opened or closed.
According to the amplifier of the present invention, even in a case where one amplifier part malfunctions, while it is repaired or replaced, the other amplifier part can substitute for the malfunctioning amplifier part.
An amplifier according to the present invention is characterized in that each amplifier part has a radiator in the above-mentioned constitution.
According to the amplifier of the present invention, heat generated by the amplifier part can be dissipated by the radiator.
An amplifier according to the present invention is characterized in that the mating portion of the box and each of the amplifier parts has a waterproof structure in the above-mentioned constitution.
According to the amplifier of the present invention, the mating portion of the box and each of the amplifier parts has a waterproof structure and hence can prevent rain or the like from entering the box to protect the amplifier part.
An amplifier according to the present invention comprises a box and an amplifier part mounted on the box in such a way that it can be opened or closed with a hinge which can be separated and that the amplifier part can be dismounted from the box by separating the hinge.
According to the present invention, when the amplifier part malfunctions because of a failure, it is dismounted from the box and can be readily replaced or repaired.
An amplifier according to the present invention is characterized in that, in the above-mentioned constitution, the hinge is separated into a box side member fixed to the box and an amplifier side member fixed to the amplifier part and that the box side member is fitted in the amplifier side member from below to prevent the amplifier part from dropping.
According to the present invention, in the case where the amplifier is placed at a high position, when the amplifier part is repaired without being dismounted from the box, even if the amplifier part is opened, the amplifier part is prevented from dropping and further can be opened towards the front of a worker, which facilitates repair work.
An amplifier according to the present invention is characterized in that, in the above-mentioned constitution, the amplifier part is a pair of amplifier parts mounted on the a left and right sides of the box such that they can be opened or closed with hinges, wherein each hinge is separated into a box side member fixed to the box and an amplifier side member fixed to the amplifier part, wherein a backup amplifier side member is fixed to a position opposite to the position where the amplifier side member of the amplifier part is fixed, and wherein the amplifier part is selectively mounted on the left side or the right side of the box by selectively fitting the amplifier part side member in service or the backup amplifier part side member in the amplifier part side member.
According to the present invention, an amplifier part dedicated to a right-hand side or a left-hand side is not required since the same amplifier part can be mounted on either side of the box, which results in a reduction in manufacturing cost. Also, when assembling the amplifier part, it is possible to assemble the amplifier part without taking into account the position where the amplifier part is to be mounted, such as right-hand side or a left-hand side, which results in a reduction in work load.
An amplifier according to the present invention comprises a box and an amplifier part mounted on the box in such a way that it can be opened or closed with a hinge having a clearance, wherein a packing made of an elastic material is fixed to the mating portion of the box and the amplifier part and wherein the amplifier part is fixed to the box in a state where the amplifier part is closed with a fastening member for pressing the amplifier part onto the box.
According to the present invention, a packing made of an elastic material for sealing such as rubber, synthetic resin or the like is fixed to the mating portion of the box and the amplifier part to form a waterproof structure for preventing the entry of rain or the like, and if the amplifier part is pressed onto and fixed to the box by the use of a fastening member such as a screw, a clip or the like in a state where the amplifier part is closed, the amplifier part and the box are pressed onto the packing of the mating portion to surely make the mating portion waterproof.
An amplifier according to the present invention comprises a box, and a pair of amplifier parts mounted on the left and right sides of the box in such a way that they can be opened or closed, wherein the left and right amplifier parts can be mounted on the opposite sides. A rubber packing is provided at the mating face of the box and each of the amplifier parts, and a radiator for dissipating heat is provided on the outside of each of the amplifier parts.
According to the amplifier of the present invention, even if one of the left and right amplifier parts malfunctions, while it is repaired or replaced, the other amplifier part can substitute for the malfunctioning amplifier part. Also, according to the amplifier of the present invention, heat generated by the amplifier part is dissipated by the radiator provided on the outside. According to the amplifier of the present invention, the packing provided on the mating portion of the box and the amplifier part can prevent the entry of rain or the like. Further, according to the amplifier parts of the present invention, the amplifier parts can be switched between the left and right amplifier parts. Therefore, when the amplifier part in service malfunctions, it can be replaced with the other amplifier part.
An amplifier according to the present invention is characterized in that, in the above-mentioned constitution, one of the pair of amplifier parts is in service and the other is used as a backup.
Also, an amplifier according to the present invention is characterized in that, in the above-mentioned constitution, the amplifier is placed outdoors at a high position in order to amplify the radio wave of a portable telephone system.
According to the amplifier of the present invention, when the amplifier part now in service malfunctions because of a failure, it can be replaced with the backup amplifier part on standby. Therefore, the operation of a radio communication system using this amplifier can be restored without being stopped for a long time.